Building a Quality Assessment Program for TB Laboratories in Haiti

Building a Quality Assessment Program for TB Laboratories in Haiti

Challenge

Controlling tuberculosis (TB) through diagnosis, treatment, and monitoring requires a network of laboratories with accurate and reliable means of testing.

In Haiti, direct smear microscopy of respiratory specimens has been the main means for diagnosing TB. As a result, quality assessments of sputum smear microscopy are essential for evaluating technical proficiency.

Background

The Laboratoire National de Santé Publique, a national public health laboratory in Haiti, was established in 2006 to serve as a national reference testing center. It provides direction and organization of quality assurance programs. In 2008, the network of microscopy centers consisted of 238 public and private centers, with only one private center providing culture and limited drug susceptibility testing.

With support from the Massachusetts Supranational TB Reference Laboratory (MSRL), the Laboratoire National has established an external quality assessment program using panel testing slides set as the first measurement of acid fast bacilli (AFB) microscopy performance in Haiti. Twenty high-volume smear microscopy centers were evaluated. The International Union Against Tuberculosis and Lung Disease (IUATLD) grading scale and scoring system were adapted for evaluation of panel testing results.

The MSRL, managed and operated by Commonwealth Medicine — the health care consulting division of UMass Medical School — has been designated as part of an international network to standardize methods for diagnosing TB and its drug-resistant strains in high incidence locations.

Solution

The initial set of 400 slides with varying AFB quantities was prepared at the MSRL. This set was comprised of five groups with various AFB loads.

Standardized panels containing five stained and five unstained slides with varying AFB quantities were validated by the MSRL and co-validated by the Laboratoire National Haiti.

The validated panels were distributed to a group of 20 high-volume microscopy centers. Results were assessed and scored. After pre-intervention measurement, on-site corrective action activities were formulated with the Laboratoire National. The Laboratoire National initiated refresher course training activities, reinforcing standardized techniques. Post-intervention performance was evaluated using a second panel, testing slide set with the same degree of challenge.

Results

Pre-intervention measurement revealed a proficiency average of 60 percent. When the least stringent scoring criteria were applied, 18 laboratories (90 percent) performed below 80 percent. This early data demonstrated performance issues.

Post-intervention measurement revealed the following:

  • Overall improvement of 27 percent
  • Number of laboratories with performance below 80 percent decreased from 18 to four (20 percent)